1. Field of The Invention
This invention relates to tree injecting devices. More particularly, it refers to a plunger type hand held device used to inject liquid chemicals into living cells of a tree.
2. Description of The Prior Art
Large standing trees are continuing to have increased value both from an ornamental and economic viewpoint. Great efforts have been exerted by man to promote the growth of trees and to save trees from infection. This has included various modes of treatment. One common method of delivering liquid fertilizer or systemic pesticide to tree is by injecting the liquid directly into the living cells beneath the cortex layer of the tree trunk. Generally a small horizontal or downwardly inclined hole is drilled in the tree trunk and the liquid is injected from a pressurized container such as described in U. S. Pat. No. 3,130,519. Additional injection methods and devices are shown in U. S. Pat. Nos. 4,011,685 and 4,144,673. In addition, friable containers or ampules are inserted into a hole drilled in a tree trunk. After breaking the ampule, the liquid flows into the living tree cells as shown in U.S. Pat. No. 3,367,065. Although the methods in the patents are useful in achieving their objections, they each have practical limitations. In the case of U. S. Pat. No. 3,130,519, the injection process requires a pressurized container and the release of the undesirable chemicals required to produce the container pressure. U. S. Pat. No. 4,011,685 describes a refillable reservoir and a polished needle. This is an expensive apparatus which can only justify its cost by repeated use. However, refilling of the reservoir with different liquids; ie, pesticide in place of a tree nutrient could lead to unwanted contamination. U. S. Pat. No. 4,144,673 describes a system requiring a plurality of injection holes in a tree. These multiple holes could provide entry of insects or microscopic contamination from bacteria or fungi. The ampule described in U. S. Pat. No. 3,367,065 requires a rather large cut into the tree and could likewise result in contamination.
A device is needed that can facilitate injection of a liquid substance into a tree's living cells without the need for multiple or large holes in the trunk and can be cheap enough to be thrown away after a single use so that future contamination problems are eliminated.